Now, roughly 20 years later, Nieh is spearheading the most significant regulatory changes in decades to ensure that this time, the nuclear revival won’t fall apart. 

Nieh’s path to leading the NRC began as a child living in New York as the son of Chinese immigrants. As he began to figure out what he wanted to do with his life, Nieh remembered watching his father work as a welder at the Indian Point nuclear power plant just 25 miles north of New York City.

Growing up, he remembered hearing about accidents at Three Mile Island in Pennsylvania or Chernobyl in Ukraine, or watching the fallout on TV, but recalled that they never struck fear in his heart.

Instead, the nuclear energy industry piqued his interest.

Following high school, Nieh studied marine engineering at the New York Maritime College, with the intention of attending the school’s nuclear program. But by the time he arrived, the program was canceled.

That didn’t put him off, as Nieh later studied at the U.S. Naval Nuclear Power School and attended Rensselaer Polytechnic Institute for graduate studies in nuclear engineering. He later earned an MBA from Johns Hopkins University.

His career with the NRC began in the 1990s, when he started as a project engineer. He has spent the next nearly 30 years touching “almost every corner of the nuclear energy ecosystem,” working with the Navy’s nuclear program, the International Atomic Energy Agency, nuclear developers, as an inspector, and then again at the NRC. 

Nieh was sworn in as an NRC commissioner in December and was designated as the next chairman by Trump less than a month later. Nieh, whose term ends in June 2029, is the first former resident inspector with the NRC to serve as a commissioner.

Having spent his entire career in the nuclear energy industry, Nieh sees the renaissance backed by the Trump administration as long overdue.

What’s driving this revival 

In May 2025, President Donald Trump signed four executive orders aimed at bolstering the nuclear energy industry. These orders were broadly meant to jumpstart the construction of nuclear reactors in order to increase the domestic energy supply and meet surging electricity demand tied to the rapid development of artificial intelligence.

At the time, Trump outlined a new target: to quadruple domestic nuclear energy capacity to 400 gigawatts by 2050.  

The executive orders called for boosting domestic mining and uranium enrichment for reactor fuel, accelerated testing and development of advanced reactors, and the overhauling and simplification of the regulatory processes for approving new nuclear energy projects. 

Specifically, Trump called on the NRC to make decisions on reactor licenses within 18 months, reform the agency’s culture and staffing structure, and undertake a wholesale review of the agency’s regulations and guidance documents. 

The agency has taken steps to deliver on each of these directives, reviewing decades-old regulations to eliminate outdated, redundant or unnecessary rules. 

Nieh explained said that federal regulators have been aware of licensing and approval delays for decades.

There was progress made with the 2024 Advance Act, which was meant to accelerate the licensing and development of next-generation reactors in numerous ways, including by lowering specific licensing application fees. Last year’s order from the executive branch, however, took it to the next level, he said. 

“The executive order, President Trump’s executive order, that was a catalyst for the most comprehensive change,” Nieh said. 

He pointed out that, while the changes are being made now, many of the reforms being made have been years in the making, with some provisions stemming back to work done in 2004. 

“I think a lot of people that have dealt with these issues for so long … they have a commission that’s working quickly,” he said. “Rules, on average, have taken anywhere from four to seven years to go from beginning to end. Now, we’re probably going to have a handful of rules that are going to be done well inside of two [years].” 

Not only is the political support there, Nieh said, the industry has public backing. 

The chairman said there has been “generational change,” with young adults no longer carrying the weight, fear, or memory associated with accidents that happened at Three Mile Island or Chernobyl.

Simultaneously, younger generations have become more concerned about climate change, making nuclear energy an attractive alternative for those seeking carbon-free solutions, he said.  

“I think the generational shift has, you know, really been a positive factor in the increased public support for nuclear power,” he said. 

Faster deadlines with fewer people 

One of the biggest challenges the NRC has faced over the last year has been meeting accelerated timelines while losing hundreds of employees. 

In May, Commissioner Bradley Crowell testified before Congress that the agency had lost 510 employees over the previous 16 months, while only adding 59 new members of staff. 

Some of this was attributed to increased competition with the private sector, work-life balance concerns, and the government-wide buyouts initiated by the Department of Government Efficiency last year. 

Nieh said the NRC saw higher-than-normal attrition in 2025, losing not only lower-level employees but also those with decades of experience, as well as the knowledge and critical skill sets needed to conduct licensing reviews or develop new rules. 

“We’re not at a point where we can’t get the work done,” Nieh said. “It’s just stressing the organization a little bit more, because you have fewer people to do the work that normally you can distribute it among more people.”

The chairman told the Washington Examiner that the agency has about 120 fewer people than what is expected for the anticipated workload next fiscal year. However, that hasn’t limited the staff’s ability to get work done, he said. 

Even with the staffing cuts, Nieh pointed out, the NRC issued a new licensing framework for advanced reactors, known as Part 53, about 21 months ahead of schedule. The agency was also able to issue a construction permit, the first in decades, for an advanced reactor being built by TerraPower in Wyoming, roughly nine months ahead of schedule. 

“We’ve done a significant number of other major licensing activities, like license extensions well inside of established schedules, as well as trying to do future license renewals in 12 months,” he said. 

“The reason why we’re able to do that is that we’re sharpening the focus on what matters most for safety,” he said. 

The agency is taking steps to build its workforce, bringing in entry-level and mid-career hires. The NRC also recently launched its Nuclear Regulatory Apprenticeship Network, which brings on recent graduates looking to start their career with the agency straight out of school. 

Nieh doesn’t view this as a massive expansion of the agency that would double in size, as it continues to review its regulatory framework to become efficient. 

“This is the beauty of some of the rule changes that we’re making,” he said. 

No ‘rubber-stamping’

Since Trump ordered the overhaul of NRC regulations and called for accelerated licensing timelines, Democrats and nuclear safety advocates have sounded the alarm, claiming the administration was threatening the agency’s independence and imposing its own agenda on the commissioners. 

This, in part, stemmed from a separate executive order signed by the president in February 2025, which required independent agencies to submit all proposed and final significant regulatory actions to the White House’s Office of Information and Regulatory Affairs for review before publication. 

This is an entirely new process for the NRC, which previously collected more input from stakeholders throughout the rulemaking process. 

Nieh explained that the reviews have primarily led to more technical questions about the rules, sometimes requiring additional clarification from the agency, such as for a cost-benefit analysis for a particular rule. 

There hasn’t been any influence from the agency regarding the language of the rules, he said. 

Concerns regarding the agency’s independence were also raised over the president’s decision to fire former Democratic Commissioner Christopher Hanson, the first commissioner to be fired since the NRC was created in 1975, and apparent pressure to “rubber-stamp” approvals. 

During a Senate hearing in September, commissioner and then-chairman David Wright told lawmakers that a Department of Energy official used the phrase “rubber-stamp,” to reference the agency would push through authorizations made by the DOE and Department of War for test reactors seeking commercial licenses.

At the time, Wright told Congress that he pushed back, insisting that the NRC doesn’t “rubber-stamp anything.” 

Fast-forward to this past April, the NRC proposed a rule that would allow the agency to leverage prior authorizations issued by the Energy and War departments for demonstration reactors into its own licensing reviews. 

Nieh told the Washington Examiner that the proposed rule does not amount to a rubber-stamp, calling that a “mischaracterization.” 

“It’s not really a foreign concept either, we have used input from Department of Energy labs and our regulatory reviews in the past,” he said. “They’ll write a technical report because we don’t have the subject matter expertise on something. So we’ll read it, we’ll confirm, ask questions, make sure it meets our requirements, and we’ll include it into our decision making. It’s not really a foreign concept. I just think all the excitement around how visible now DOE and NRC are working together has just caused some concerns.” 

Since being sworn in as chair, Nieh has prioritized transparency, particularly between the DOE and the NRC, in order to uncover overlapping regulations or processes. 

During Monday’s interview, Nieh even took a moment to ask staff if his office could develop a “communication tool” that explains the Energy Department’s authorization process compared to the NRC to better lay out the differences and collaboration. 

Purpose not pressure

In response to criticism that the administration has imposed its agenda on the commission and influenced it to accelerate the build-out of nuclear power for advancing AI, Nieh said he has felt no pressure. 

Instead, he called the urgency “purpose.” 

Nieh said that nuclear energy has become essential not only for the energy sector but also for national security, as China has rapidly deployed dozens of new reactors within the last 30 years while the U.S. has only built three. 

If the U.S. fails to deliver in the industry, he said, allies will turn to China to purchase reactors and accept the geopolitical consequences that come along with it. 

“I feel so empowered by this moment right now,” he said. “This is, really in my view, the most consequential moment for nuclear energy in America in nearly 50 years.”

Given the combined interest from the administration, energy and technology industries, and even the general public, Nieh said the conditions are “ideal” for the U.S. to be the global leader for nuclear energy. 

“I want to make that happen,” he said. “So that’s the purpose I feel. So I don’t feel any pressure. It’s just, like this is the moment for America.”

SMALL NUCLEAR REACTORS COULD BE OPERATIONAL BY 2030, REGULATOR SAYS IN FIRST INTERVIEW

Every day outside his office window, Nieh can see the third agency building built for a nuclear energy revival that never came to fruition 20 years ago.

To him, it serves as a physical reminder of how close the U.S. got then and how the current opportunity can’t be wasted.

“That building now stands as somewhat of a ‘memorial’ to the renaissance that never happened,” Nieh said. “But what’s different now is we’re not going to build a new building. Because of the path set by the Advance Act and the catalyst of President Trump’s EO, we’re going to fundamentally work smarter and focus on what’s most important for safety.”